U.S. patent number 5,418,056 [Application Number 07/616,901] was granted by the patent office on 1995-05-23 for polymer composite with dispersed fine grains and a method for manufacturing the same.
This patent grant is currently assigned to Mitsuboshi Belting Ltd.. Invention is credited to Shigehito Deki, Kazuo Goto, Hajime Kakiuchi, Toru Noguchi, Yoshio Yamaguchi.
United States Patent |
5,418,056 |
Noguchi , et al. |
May 23, 1995 |
Polymer composite with dispersed fine grains and a method for
manufacturing the same
Abstract
A polymer composite includes a thermoplastic plastic polymer
having a fine grain metal or metal oxide dispersed therein.
Preferably, the fine grains has a size of about 1,000 nm or less. A
method of making the polymer composite by adhering a metal layer to
a thermoplastic polymer layer in a thermodynamically
nonequilibrated condition followed by relaxation of the polymer
layer to obtain thermodynamic equilibrium which causes the metal
layer to be absorbed by the polymer layer as fine grains is also
disclosed.
Inventors: |
Noguchi; Toru (Fukaehonmachi,
JP), Goto; Kazuo (Amagasaki, JP),
Yamaguchi; Yoshio (Hyogo, JP), Kakiuchi; Hajime
(Itami, JP), Deki; Shigehito (Hyogo all of,
JP) |
Assignee: |
Mitsuboshi Belting Ltd. (Kobe,
JP)
|
Family
ID: |
26548443 |
Appl.
No.: |
07/616,901 |
Filed: |
November 21, 1990 |
Foreign Application Priority Data
|
|
|
|
|
Nov 24, 1989 [JP] |
|
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1-305752 |
Oct 5, 1990 [JP] |
|
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2-268709 |
|
Current U.S.
Class: |
428/323; 264/131;
264/134; 428/329; 428/328; 427/296; 427/248.1; 427/205; 427/202;
427/201; 427/195; 427/192; 427/191; 427/190; 427/189; 264/346;
264/235; 427/250 |
Current CPC
Class: |
C08K
3/22 (20130101); B01J 31/06 (20130101); B01J
37/0219 (20130101); C08K 3/08 (20130101); Y10T
428/257 (20150115); Y10T 428/25 (20150115); B01J
23/38 (20130101); B01J 37/0238 (20130101); Y10T
428/256 (20150115) |
Current International
Class: |
B01J
37/00 (20060101); B01J 31/06 (20060101); B01J
37/02 (20060101); C08K 3/08 (20060101); C08K
3/00 (20060101); C08K 3/22 (20060101); B28B
011/06 (); B05D 003/02 (); B32B 005/16 () |
Field of
Search: |
;428/323,328,329,458,475.5,462
;427/201,202,205,189,195,248.1,250,296,446,453,566,190,191,192
;264/131,134,235,346,348 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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|
|
|
|
0125617 |
|
May 1984 |
|
EP |
|
0318196 |
|
Nov 1988 |
|
EP |
|
144029 |
|
Nov 1980 |
|
JP |
|
1024832 |
|
Jan 1989 |
|
JP |
|
314781 |
|
Jul 1969 |
|
SU |
|
WO90/11890 |
|
Oct 1990 |
|
WO |
|
Other References
"Organic Films COntaining Metal Prepared By Plasma Polymerization"
by K. Kashiwagi, et al., J. Vac. Sci. Technol. A5(4), Jul./Aug.
1987. pp. 1828-1830..
|
Primary Examiner: Nakarani; D. S.
Assistant Examiner: Le; H. Thi
Attorney, Agent or Firm: Wood, Phillips, VanSanten, Clark
& Mortimer
Claims
We claim:
1. A polymer composite comprising a thermoplastic polymer in a
thermodynamically equilibrated state and fine grains of at least
one metal or metal oxide dispersed and separated from each other
within the thermoplastic polymer, the fine grains having a grain
size of about 1,000 nanometers or less, the fine grains being
dispersed and separated by relaxation of a solid thermoplastic
polymer layer from a thermodynamically nonequilibrated state having
a metal or metal oxide layer on a surface of the thermoplastic
polymer layer to the thermodynamically equilibrated state.
2. The polymer composite in accordance with claim 1 wherein the
grain size is about 300 nanometers or less.
3. The polymer composite in accordance with claim 1 wherein the
grain size is about 100 nanometers or less.
4. The polymer composite in accordance with claim 1 wherein the
fine grains are selected from the group consisting of gold, silver,
platinum, copper, iron, zinc, cerium and oxides thereof.
5. The polymer composite in accordance with claim 1 wherein the
thermoplastic polymer is selected from the group consisting of
nylons, high density polyethylenes, low density polyethylenes,
poly(vinylidene fluorides), poly(vinyl chlorides), and
polyoxymethylenes.
6. The polymer composite in accordance with claim 1 wherein the
metal or metal oxide layer is being deposited on the thermoplastic
layer at a rate of at least about 50 nanometers per minute.
7. The polymer composite in accordance with claim 6 with the metal
or metal oxide layer being deposited at a rate of about 130 to
about 2,000 nanometers per minute.
8. A method for manufacturing a polymer composite comprising the
steps of:
providing a substrate;
forming a layer of solid thermoplastic polymer in a
thermodynamically nonequilibrated state by vacuum evaporation on
the substrate;
applying a metal or metal oxide layer to the surface of the polymer
layer, the metal or metal oxide layer being capable of forming fine
grains of the metal or metal oxide in the solid polymer layer;
and
relaxing the polymer layer at a temperature less than the melting
temperature of the polymer to maintain the polymer layer in a
solid, non-molten state to achieve thermodynamic equilibrium of the
polymer layer and disperse the fine grains in the solid polymer
layer, the fine grains being of about 1,000 nanometers or less in
size.
9. The method in accordance with claim 8 wherein the metal or metal
oxide layer is applied at a thickness that results in substantially
all of the metal or metal oxide layer being dispersed in the
polymer layer upon relaxation.
10. The method in accordance with claim 8 wherein the metal or
metal oxide layer is applied to the polymer layer by a vacuum
evaporation method.
11. The method in accordance with claim 8 wherein the step of
applying the metal or metal oxide layer is performed at a rate of
at least about 50 nanometers per minute.
12. The method in accordance with claim 11 wherein the metal or
metal oxide layer is applied at a rate of about 130 to about 2,000
nanometers per minute.
13. The method of claim 8 wherein the relaxing step is performed at
a temperature greater than the glass transition temperature of the
polymer.
14. A polymer composite made in accordance with the method of claim
8.
15. A method of manufacturing a polymer composite of fine metal or
metal oxide grains dispersed in a thermoplastic polymer, the method
comprising the steps of:
forming a solid thermoplastic polymer layer in a thermodynamically
nonequilibrated state by melting and immediate solidification;
applying a metal or metal oxide layer to the surface of the
thermoplastic polymer layer, the metal or metal oxide layer being
capable of forming fine grains in the solid polymer layer; and
relaxing the thermoplastic polymer layer at a temperature less than
the melting temperature of the polymer to achieve thermodynamic
equilibrium of the thermoplastic polymer layer and disperse the
fine grains in the solid plastic layer, the fine grains having a
size of about 1,000 nanometers or less.
16. The method in accordance with claim 15 wherein the metal or
metal oxide layer is applied at a thickness that results in
substantially all of the metal or metal oxide layer being dispersed
in the polymer layer upon relaxation.
17. The method in accordance with claim 15 wherein the step of
applying the metal or metal oxide layer is performed at a rate of
at least about 50 nanometers per minute.
18. The method in accordance with claim 17 wherein the metal or
metal oxide layer is applied at a rate of about 130 to about 2,000
nanometers per minute.
19. A polymer composite made in accordance with the method of claim
17.
Description
TECHNICAL FIELD
This invention relates to a polymer composite with fine grains
dispersed therein and a method for manufacturing the composite.
More particularly, this invention relates to a polymer composite
containing fine grains of a metal or metal oxide having a size of
about 1,000 nm or less and a method for manufacturing the
composite.
BACKGROUND OF THE INVENTION
Presently, various functional polymers with conductivity have been
developed, including a group of polymers utilizing .pi. conjugated
electrons. These polymers are represented by
phosphorus-paraphenylene, phosphorus-paraphenylenevinylene,
phosphorus-thiophene, phosphorus-aniline, phosphorus-pyrrole, and
the like and are known to have a conductivity ranging from 1 to
1.times.10.sup.5 Siemens per centimeter (S/cm), which is
approximately equal to the conductivity of metals.
However, once conjugated bonds have been formed, the
above-mentioned conductive polymers become insoluble even in a
solvent and therefore are very difficult to process by molding. The
polymers are difficult to process into thin film, film, wire, and
the like. Also, these polymers experience a decline of conductivity
induced when they are left in the air for many hours.
Another polymer material having a polymer matrix packed with such
conductors of metal fine grains such as metal powder, metal fiber,
carbon black, and the like only has a conductivity of
1.times.10.sup.-4 to 1 S/cm. In the polymer material, conductivity
is ensured because the conductors are in contact with each other.
Unfortunately, the degree of the contact varies greatly in the
matrix which results in resistance distribution.
Since metal fine grains permit most of their atoms to be used to
form a surface and they have a large proportion of atoms exposed on
the surface, it is known that they are highly active physically as
well as chemically and have markedly different properties from bulk
metals that are not fine grains. Also because of the huge surface
areas that these polymer materials possess, which are caused by the
metal fine grains, these polymer materials have been conventionally
attempted to be used for catalysts, heat exchange system, specific
conduction material, magnetic material, photoelectric conversion
material, vital material, drug material, and the like.
Due to their high reactivity, the metallic fine grains are
difficult to handle; for example, they are readily ignited,
exploded or they themselves are resintered, aggregated, or make
their sizes varied. In addition, they also change in physical and
chemical properties which leads to very few industrial
application.
SUMMARY OF THE INVENTION
The present invention is directed to a polymer composite including
a thermoplastic polymer and fine grains of at least one metal or
metal oxide dispersed and separated within the thermoplastic
polymer. The fine grains have a grain size of about 1,000
nanometers (nm) or less. The present invention is also directed to
a method of manufacturing the polymer composite that includes the
steps of providing a ground, forming a layer of a thermoplastic
polymer in a thermodynamically nonequilibrated state on the ground,
applying a metal layer to the surface of the polymer layer and
relaxing the polymer layer to achieve thermodynamic equilibrium of
the polymer layer which causes fine grains of the metal layer to be
dispersed in the polymer layer. The polymer layer can be formed by
vacuum evaporation on or by melting the polymer followed by rapid
cooling and solidification.
As a result that the present inventors paid attention to the
foregoing problems and did their utmost to obtain a stable and
highly conductive polymer material, they have found the unique
phenomena that the metallic conductors penetrate naturally into a
polymer in a state of fine grains with a size of about 1,000 nm or
less without being sparingly packed in the polymer and that these
fine grains are quite stably dispersed independently from one after
another, thus arriving at this invention. The density of the fine
grains in the polymer layer of the composite contributes to the
desired results.
A polymer composite, which can also be referred to as a polymer
complex, of this invention has the fine grains of a metal or metal
oxide dispersed therein. Said fine grains are dispersed in a state
of separation from each other in the polymer layer, possessing an
excellent conductivity even in this dispersed condition. In
addition, even though the fine grains of the metal or metal oxide
present in the polymer layer are small in volume, the polymer
composite exhibits a sufficient conductivity, is applicable as a
bonding material and possesses photoelectric effect.
Moreover, in a method for manufacturing a polymer composite with
the above-mentioned fine grains dispersed therein, after a polymer
is melted, the resulting material is cooled rapidly and solidified,
thus forming a thermodynamically nonequilibrated polymer layer.
With the equilibration, that is, relaxation of said polymer layer,
a metal layer provided on the surface of said layer can be diffused
and penetrated into the polymer layer and can also be dispersed
homogeneously in a highly physically and chemically stable state
without causing the ignition, explosion or resintering of the fine
grains. In addition, this composite exhibits chemical and physical
stability over time, less resistance distribution and, moreover,
has the effect that the polymer layer can be readily formed into
thin film, film, wire material, and the like.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a longitudinal cross-sectional view showing a polymer
layer formed on a ground;
FIG. 2 is a longitudinal cross-sectional view showing a metal layer
stuck onto a polymer layer;
FIG. 3 is a longitudinal cross-sectional view showing a polymer
layer with a metal layer after heating;
FIG. 4 is a longitudinal cross-sectional view of a present polymer
composite obtained by a method in accordance with this
invention;
FIG. 5 is a diagram showing the dispersion of gold fine grains
depicted from a transmission electron microphotograph of a polymer
composite obtained in accordance with EXAMPLE 1;
FIG. 6 is an X-ray diffraction pattern diagram of a polymer
composite obtained in accordance with EXAMPLE 1;
FIG. 7 is a diagram showing the relation between the frequency and
impedance Z of a polymer composite obtained in accordance with
EXAMPLE 1;
FIG. 8 is a diagram showing the relation between the frequency and
phase angle .theta. of said composite;
FIG. 9 is a thin film X-ray diffraction pattern of a laminate of a
polymer layer, metal film as obtained in accordance with the
EXAMPLE 2 and a polymer composite;
FIG. 10 is a diagram showing the grain size distribution of gold
fine grains which are dispersed in a polymer composite;
FIG. 11 is a diagram showing the grain size distribution of silver
fine grains which are dispersed in a polymer composite;
FIG. 12 is a diagram snowing the grain size distribution of copper
oxide fine grains which are dispersed in a polymer composite;
and
FIG. 13 is a diagram to explain a measuring method of photoelectric
effect in EXAMPLE 10.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
A polymer composite of the present invention has fine grains
dispersed therein. The fine grains have a size of 1,000 nanometers
(nm) or less and are selected from a group consisting of metals or
metal oxides and are dispersed independently from each other. A
method for manufacturing a polymer composite with fine grains
dispersed in accordance with this invention includes the following
steps: melting a polymer material; rapidly solidifying the melted
polymer to form a thermodynamically nonequilibrated polymer layer;
providing a metal film stuck onto the surface of this polymer
layer; and relaxing the polymer layer until it reaches equilibrium
which results in metal or metal oxide fine-grains from said metal
layer penetrating and dispersing in the polymer layer.
Alternatively, the thermodynamically nonequilibrated polymer layer
can be produced by vacuum evaporation.
The fine grains dispersed in the polymer can be present in an
amount in the range of about 0.1 to about 80 volume percent.
The steps of the method in accordance with this invention are
described in more detail in conjunction with FIGS. 1 to 4.
(1) As shown in FIG. 1, the first step is to form a polymer layer
in a thermodynamically nonequilibrated state; this step can be
accomplished using, e.g., a vacuum evaporation method or a melting
and rapid solidification method.
The vacuum evaporation method that is exemplified by heating a
polymer material in a vacuum for melting and evaporation and then
solidifying said polymer layer 2 on a ground 1. With the vacuum
evaporation method, using a known vacuum evaporator, a polymer
layer can be obtained on a ground such as glass or the like at the
vacuum of 1.times.10.sup.-4 to 1.times.10.sup.-6 Torr and the
evaporation speed of 0.1 to 100 micrometers/minute (.mu.m/min),
preferably 0.5 to 5 .mu.m/min.
The melting and rapid solidification method is exemplified by
melting a polymer material at a temperature above the temperature
of melting and immediately putting the material into a bath of
liquid nitrogen or the like in the molten state for rapid cooling
and then solidifying. Within the bath is ground 1, i.e., a
substrate upon which the polymer layer 2 solidifies. In the melting
and rapid solidification method the polymer material is melted and
cooled at a cooling rate above the critical cooling temperature
peculiar to the polymer material, and is then put in, for example,
liquid nitrogen, to obtain the polymer layer.
The polymer layer 2 thus obtained is formed on the ground 1 in a
thermodynamically nonequilibrium state and changes to a
thermodynamically equilibrium state over time.
The polymer material used herein is a conventional thermoplastic
polymer, for example, nylon 6, nylon 66, nylon 11, nylon 12, nylon
69, high density polyethylenes (HDPE), low density polyethylenes
(LPDE), poly(vinylidene fluorides) (PVDF), poly(vinyl chlorides),
and polyoxymethylenes.
(2) Next, as shown in FIG. 2, the polymer layer 2 in a
thermodynamically nonequilibrium state has a metal layer 3 stuck
onto the surface of said polymer layer 2. In this step, the metal
layer 3 is laid on the polymer layer 2 by evaporating the metal
layer 3 to the polymer layer 2 using the above-mentioned vacuum
evaporator or by sticking metal foil or plate directly onto the
solidified polymer layer 2. Representative metal materials include
gold, silver, platinum, copper, iron, zinc, cerium, their oxides
and the like.
(3) The polymer layer 2 is brought into an equilibrium state by
heating to a temperature between the glass transition temperature
and the melting temperature of the polymer or leaving naturally. In
this step, it is preferable to keep the polymer layer with the
adhered metal layer at a temperature below the melting temperature
of the polymer material in an isothermal water bath and thus
promote its state of relaxation. As a result, the metal of the
metal layer 3, as shown in FIG. 3, becomes the fine grains 4 of the
metal or metal oxide that diffuse and penetrate into the polymer
layer 2. The fine grains 4 have a grain size of about 1,000 nm or
less, preferably about 300 nm or less, and more preferably about
100 nm or less. This state of diffusion and penetration continues
until the polymer layer 2 is completely relaxed, and the metal
layer 3 adhering to the polymer layer 2 is reduced in its thickness
and, preferably, finally disappears. (See FIGS. 3 and 4).
Accordingly, it is preferable to adjust the thickness of the metal
layer 3 in order that the metal layer entirely becomes the fine
grains 4 of the metal or metal oxide and its totally dispersed in
the polymer layer 2.
Said fine grains 4 include the above-mentioned metals, and their
oxides such as Cu.sub.2 O, Fe.sub.3 O.sub.4 and ZnO.
Furthermore, when the polymer layer 2 is heated in this step, it is
seen that the polymer layer 2 assumes its inherent color due to its
interaction with the metal or metal oxide and that the fine grains
4 of the metal or metal oxide have penetrated into the polymer
layer 2. In addition, the color can vary depending on the kind of
metal or metal oxide, the fine grain size of the metal or metal
oxide and the type of polymer utilized.
As shown in FIG. 4, a polymer composite 5 with the fine grains of
the metal or metal oxide obtained in the above manner has the fine
grains 4 separated and dispersed in an independent state. In other
words, the polymer composite 5 has good conductivity despite the
fact that the fine grains of the metal or metal oxide are not in
contact with each other and are present in a relatively small
amount. In addition, since the fine grains 4 of the metal or metal
oxide are dispersed stably in the polymer layer 2, the polymer
composite 5 in accordance with this invention has superior acid
resistance, maintains stable physical property values such as
conductivity, and possesses an excellent stability over time.
The polymer composite 5 can be a conductive polymer or a conductive
paste, with these fine grains dispersed therein.
The polymer composite has the extremely large catalytic activity of
a fine-grained metal and also takes a form in which the fine grains
of the metal or metal oxide are covered with a polymer. It can be
utilized in the following ways: stably maintained catalyst;
magnetic memory in which a mass storage can be expected because of
a fine-grained metal or metal oxide; light or heat response
material utilizing the changes in the structure and distance
between a polymer and the above-mentioned fine grains caused by
stimulation of light or heat; optical material such as liquid
crystal color display material due to the presentation of clear and
inherent colors by proper selection of the types of polymer and
metal; sintering accelerator and bonding material utilizing a
decline in the sintering temperature of a powdered metal caused by
the fine grains of the metal; heat exchange film due to a composite
of a polymer and the fine grains of a metal or metal oxide
utilizing the large specific heat capacity of the fine grains; bulk
condenser material; and various gas sensors.
Next, EXAMPLES of the present invention will be described in
further detail with reference to its embodiments. These EXAMPLES
are presented by way of illustration, and not limitation.
EXAMPLE 1
A first sample was prepared with a vacuum evaporator into which a
predetermined polymer pellet was put into a tungsten board,
followed by a reduction of pressure to 1.times.10.sup.-6 Torr.
Then, the tungsten board was heated under vacuum with the
inter-electrode application of a voltage to melt the polymer. Thus,
a polymer layer, which is an evaporated film with a thickness of
about 5 .mu.m, was produced at a speed of about 1 .mu.m/min and
vacuum level of 1.times.10.sup.-4 Torr to 1.times.10.sup.-6 Torr on
a ground (a glass sheet) placed on the upper part of a table. The
molecular weight of this polymer layer represented about 1/2 to
1/10 that of the pellet. Then, a gold wire was coiled round the
tungsten wire and melted by heating for evaporation in a vacuum of
1.times.10.sup.-4 to 1.times.10.sup.-6 Torr, causing a gold
evaporated film to be stuck onto the polymer layer. The glass plate
with this polymer layer and film stuck thereon was taken out from
the vacuum evaporator and maintained for 30 minutes in an
isothermal bath kept at 100.degree. C., thus yielding a polymer
composite. As a result, the gold color of the film surface
disappeared, so that the composite as a whole turned to be clear
and red.
Furthermore, FIG. 5 shows a state of dispersed gold fine grains 4,
which was depicted from a transmission electron microphotograph of
a composite using nylon 11 as the polymer layer 2. According to
this picture, gold takes the form of fine grains with a size of 1
to 10 nm and is distinctly dispersed in nylon 11. FIG. 6 further
shows an X-ray diffraction pattern of said sample, from which it
can be seen that a peak of diffraction appears at the same
diffraction angle as that of gold evaporated on glass, revealing
the same structure as bulk gold, but a large width of the
diffraction peak gives evidence that gold became fine grains.
For comparative examples, each polymer pellet was melted at a
temperature above its melting temperature and then cooled slowly to
form a polymer layer with a thickness of 10 .mu.m in a
thermodynamically equilibrium state. Each layer had gold evaporated
thereon, then was taken out from the vacuum evaporator, and was
allowed to stand for 30 minutes in an isothermal bath maintained at
100.degree. C. There was no change in either the layer form or the
gold color of the film surface. Table 1 presents each sample with
reference to the construction, film coloration after heating, and
size of gold fine grains measured with the transmission electron
microscope.
TABLE 1
__________________________________________________________________________
Embodiment Comparative example 1-1 1-2 1-3 1-4 1-1 1-2 1-3 1-4
__________________________________________________________________________
Polymer nylon 11 nylon 12 PVDF HDPE nylon 11 nylon 12 PVDF HDPE
Manufacturing evaporation slow cooling after melting method of
polymer layer Metal gold gold gold gold gold gold gold gold
Manufacturing evaporation evaporation method of metal film Ground
glass glass glass glass none none none none Color of film clear and
clear and clear and clear and clear and clear and clear and clear
and after heating red red red dark red white white white white
Grain size of 1-10 1-10 1-10 1-100 -- -- -- -- metal (nm)
__________________________________________________________________________
(Assessment of conductivity)
The conductivity of each of said samples was assessed. First, a
laminated film obtained by evaporating nylon 11, then gold to the
indium tin oxide (ITO) surface of ITO glass was cut into two
halves, stuck together so the gold evaporated film surfaces came
into contact with each other, followed by heat treatment at
100.degree. C. for 30 minutes to bond the above two halves.
Aluminum foil was fitted to both ITO surfaces by silver paste, and
impedance Z and phase angle .theta. were measured with an LCR
meter. The results are shown in FIGS. 7 and 8. According to these
figures, when gold fine grains represent 0.04 vol %, both impedance
Z and phase angle .theta. are large, whereas if they account for as
small as 0.09 vol %, impedance Z ranges from 0.1 to 100 kilohertz
(Khz), and phase angle .theta. is almost zero. This clarifies that
gold fine grains exhibit conductivity despite their dispersion and
independence from each other, leading to a presumption that a
tunnel current flows between gold fine grains.
EXAMPLE 2
Using the same vacuum evaporator as in EXAMPLE 1, three kinds of
samples were produced by laying the polymer layer of nylon 11 with
a thickness of about 5 .mu.m on glass sheets and the evaporation
films of gold, silver and copper, respectively, on the polymer
layers. These samples were then maintained at 120.degree. C. for 10
minutes in an isothermal bath to obtain the composites of this
invention. The vacuum evaporation was preformed at a vacuum level
range of 1.times.10.sup.-4 to 1.times.10.sup.-6 Torr upon
evaporation of the polymer and metal and the evaporation speed of
the polymer was 1 .mu.m/min.
For the three kinds of samples thus obtained, their X-ray
diffraction patterns were measured with a thin film X-ray
diffraction apparatus with an angle of incidence of 0.5.degree.
(RINT 1200, Rigaku Denki Co., Ltd.). The results are shown in FIG.
9.
In such X-ray diffraction patterns, the solid lines show the
laminates of polymer film and metal film, and the dotted lines show
composites after said laminates were maintained at 120.degree. C.
for 10 minutes in the isothermal bath. According to this figure, in
any patterns shown by solid lines the diffraction peaks of their
respective metal and nylon 11 appear, revealing the construction
made by laminating metal evaporated film and the polymer layer of
nylon 11. In each pattern shown by dotted lines, the diffraction
peak width (half-value width) of each metal is large, demonstrating
that each metal has been changed into fine grains and are dispersed
in nylon 11.
When copper was used, copper was changed into Cu.sub.2 O (copper
oxide), the fine grains of which were found to be dispersed in
nylon 11.
EXAMPLE 3
Next, a polymer layer was formed on a glass plate by varying the
vacuum evaporation speed of nylon 11 and then laminating with metal
(gold) evaporated film to produce samples, each of which was in
turn maintained at 120.degree. C. for 10 minutes to obtain a
polymer composite. Table 2 displays the vacuum evaporation speed of
nylon 11 and the state of the fine-grained gold in the polymer
composite.
TABLE 2
__________________________________________________________________________
Evaporation Presence of metal Thickness of nylon 11 speed
dispersion State of dispersion State of nylon 11 (.mu.m)
__________________________________________________________________________
50 nm/min yes heterogeneous wax-like 5 130 nm/min yes homogeneous
film-like 5 800 nm/min yes homogeneous film-like 5 2000 nm/min yes
homogeneous film-like 5 1500 nm/sec yes homogeneous film-like 20
__________________________________________________________________________
In accordance with the above results, when the evaporation speed of
nylon 11 was as low as 5 nm/min, gold formed fine grains were
dispersed in the polymer layer but were heterogeneously. In
addition, at this evaporation speed the polymer layer of nylon 11
took a wax-like state and exhibited adhesiveness.
EXAMPLE 4
The next study was made to determine whether metal fine grains
would penetrate into the polymer layer due to the effect of the
ground. In the same manner as in the previous EXAMPLE 1, first
sample, the polymer layer of nylon 11 was produced on various
grounds by the evaporation method with gold film further applied
thereon by the evaporation method. The polymer layer and film were
maintained at 100.degree. C. for 30 minutes in the isothermal bath.
The coloration of the polymer layer and the size of gold fine
grains penetrating into the polymer layer were measured with the
transmission electron microscope. The results are shown in Table
3.
These results reveal that the diffusion and penetration by gold
fine grains into the polymer layer took place without being
effected by the material used as the ground.
TABLE 3 ______________________________________ Embodiment 4-1 4-2
4-3 4-4 4-5 ______________________________________ Ground Glass ITO
KCI single gold polypro- Glass crystal plate pylene film Color of
clear and clear and clear and clear and clear and film red red red
red red Grain 1-10 1-10 1-10 1-10 1-10 size of metal (mm)
______________________________________
EXAMPLE 5
The effects of the metals used was then studied using samples
produced by the previously described method of EXAMPLE 1. A polymer
layer of nylon 11 was first produced on each glass ground by the
evaporation method, followed by laying the thin layers of various
metals thereon by the evaporation method to produce the samples.
After maintaining the samples at 100.degree. C. for 30 minutes in
the isothermal bath, the coloration of the polymer layer and the
size of the fine grains of each metal or metal oxide penetrating
into the polymer layer were measured with the transmission electron
microscope. The results are shown in Table 4.
TABLE 4
__________________________________________________________________________
Embodiment 5-1 5-2 5-3 5-4 5-5 5-6
__________________________________________________________________________
Metal gold silver iron zinc cerium copper Color of film clear and
clear and clear and clear and clear and clear and red yellow dark
dark red yellow yellow yellow yellow green Grain size of 1-10 1-10
1-100 1-100 1-10 1-20 metal or metal oxide (nm)
__________________________________________________________________________
According to the above data, there occurred the diffusion and
penetration by metals or metal oxides into the polymer layer
irrespective of the kinds of metals.
In addition, the grain size distribution of the fine grains of
gold, silver and copper oxide, respectively, was observed from the
transmission electron microphotographs, the results being shown in
FIG. 10 (gold fine grains), FIG. 11 (silver fine grains), and FIG.
12 (copper oxide fine grains).
These results show that the average grain sizes of gold and silver,
respectively, are smaller than that of copper oxide.
EXAMPLE 6
Each kind of polymer was put into the space formed by two glass
plates and a thickness-adjusting spacer placed between said glass
plates, left in an isothermal bath for melting, and immediately put
into liquid nitrogen for rapid cooling and solidification, thus
leading to the production of a film-like, thermodynamically
nonequilibrium polymer layer with a thickness of about 10 to about
100 .mu.m. Then, gold was vacuum-evaporated into the polymer layer
in the same manner as in EXAMPLE 1, resulting in a laminated film
which was maintained at 100.degree. C. for 30 minutes in the
isothermal bath.
The state of coloration of the above-mentioned polymer layer after
heating and the grain size of gold fine grains were examined. The
results are shown in Table 5.
The production of polymer layers in the comparative examples was
performed by cooling the polymers, which were melted in the
isothermal bath, slowly at room temperature. The metal film was
applied by the vacuum evaporation method as in this EXAMPLE.
Thus, metal fine grains were also diffused and penetrated into
polymer layers obtained by the method of rapidly solidifying the
polymers melted.
TABLE 5
__________________________________________________________________________
Embodiment Comparative example 6-1 6-2 6-3 6-4 6-1 6-2 6-3 6-4
__________________________________________________________________________
Polymer nylon 11 nylon 12 nylon 69 HDPE nylon 11 nylon 12 nylon 69
HDPE Metal gold gold gold gold gold gold gold gold Color of film
clear and clear and clear and clear and clear and clear and clear
and clear and after heating red red red dark red white white white
white Grain size of 1-10 1-10 1-10 1-100 -- -- -- -- metal (nm)
__________________________________________________________________________
EXAMPLE 7
Like in the previous EXAMPLE 1, the polymer layers of nylon 11 and
nylon 12, respectively, were produced on a glass ground by the
vacuum evaporation method and, moreover, the polymer layers of
nylon 11 and nylon 12, respectively, were produced on a glass
ground by rapidly cooling and solidifying them with liquid nitrogen
as in EXAMPLE 6. For these samples, the polymer layers were laid on
top of another so as to face each other, and with foil with a
thickness of 0.2 .mu.m allowed to lie between these polymer layers,
a pressure of 1 kg/cm.sup.-2 was placed on the glass ground to have
the gold foil adhere to the polymer layers.
After each of the above samples was maintained at 100.degree. C.
for one hour in the isothermal bath, the coloration of the polymer
layer and the grain size of metal fine grains penetrating into the
polymer layer were measured with the transmission electron
microscope. The results are shown in Table 6.
In the comparative examples, the same measurements were made using
the film obtained by melting and slow cooling.
TABLE 6 ______________________________________ Embodiment
Comparative example 7-1 7-2 7-1 7-2
______________________________________ Polymer nylon 11 nylon 12
nylon 11 nylon 12 Metal gold gold gold gold Color of film clear and
clear and clear and clear and after heating red red white white
Grain size of 1-10 1-10 -- -- metal (nm)
______________________________________
It is understood that metal fine grains were also diffused and
penetrated into the polymer layer by the method of sticking metal
foil directly onto the polymer layer.
EXAMPLE 8
The next description will be made about an EXAMPLE of this
invention using the polymer composite as a bonding material.
First, a bonding material was obtained by the same method as that
in EXAMPLE 2, using a polymer composite with gold fine grains
dispersed in 10 vol % in nylon 11 and a polymer composite with 18
vol % Cu.sub.2 O dispersed in nylon 11 and which are taken off from
the ground glass plate.
After the above material was laid on one bonded area (40
mm.times.10 mm) of a stainless steel plate that was 60 mm long, 10
mm wide and 0.1 mm thick, the bonding material was melted by
heating and then applied to the whole surface with another
stainless steel plate laid on the first plate. Next, this was
sandwiched between two iron plates with a thickness of 5 mm, and
the four corners were screwed at a clamping torque of 40
kilogram-meter (kg-m), followed by heating at a predetermined
temperature of Table 7 for 10 minutes to have the two stainless
steel plates bonded to each other.
The bonding material used in the comparative EXAMPLE 8-1 had gold
grains with an average grain size of 0.5 to 2 .mu.m dispersed in 50
wt % in liquid paraffin. The bonding material used in the
comparative EXAMPLE 8-2 had copper grains with a mean grain size of
10 to 20 .mu.m dispersed in 50 wt % in liquid paraffin.
The bonding strength of the stainless steel plates thus obtained
was measured with a tension tester. The results, in kilograms, are
shown in Table 7. Furthermore, by polishing the bonded surface of
each taken off stainless steel plate, the existence of a substance
on said polished surface was confirmed from a peak of X-ray
diffraction obtained by the thin film X-ray diffraction method with
an angle of incidence of 0.5.degree., thus allowing the study of
whether the metal in the bonding material caused metalizing. Table
8 shows the results.
TABLE 7
__________________________________________________________________________
(kg) Embodiment Comparative example 8-1 8-2 8-1 8-2
__________________________________________________________________________
Bonding Nylon 11 Nylon 11 gold grain/liquid copper grain/liquid
material gold fine grain Cu.sub.2 O fine grains paraffin paraffin
10 vol % 18 vol % Heating 700.degree. C. 40 40 failure failure
tempera- 750.degree. C. 45 30 failure failure ture 800.degree. C.
45 55 failure failure 900.degree. C. -- 66 failure failure
__________________________________________________________________________
TABLE 8
__________________________________________________________________________
Heating Embodiment 8-1 Embodiment 8-2 temperature Metallizing X-ray
diffraction peak Metallizing X-ray diffraction peak (.degree.C.)
Yes or No Au Nylon 11 Yes or No Cu Cu.sub.2 O CuO Nylon 11
__________________________________________________________________________
700 .smallcircle. .smallcircle. x x x x .smallcircle. x 750
.smallcircle. .smallcircle. x .smallcircle. .smallcircle.
.smallcircle. .smallcircle. x 800 .smallcircle. .smallcircle. x
.smallcircle. .smallcircle. .smallcircle. .smallcircle. x 900
.smallcircle. .smallcircle. x .smallcircle. .smallcircle. .DELTA.
.DELTA. x
__________________________________________________________________________
Note: among Xray diffraction peaks, x: not present .DELTA.: little
present .smallcircle.: present
According to the above results, the polymer composite in accordance
with this invention can be fully used as a bonding material because
nylon 11 is decomposed and evaporated during heat treatment,
leading the metal to provide metalizing on the stainless steel
plate.
EXAMPLE 9
A method of sticking a polymer composite of this invention onto a
bonded material was studied next. In this EXAMPLE, a polymer
composite with 18 vol % Cu.sub.2 O dispersed in nylon 11 was stuck,
by the same vacuum evaporation method as in EXAMPLE 2, to a polymer
composite with 18 vol % Cu.sub.2 O dispersed in nylon 11 obtained
in EXAMPLE 8 (which was taken off in a film shape from the ground
glass plate). A paste product was obtained by dissolving the
polymer composite in methacresol at a weight ratio of 1:1, and
applying the paste to the surface of a bonded material, thus
leading to bonding of stainless steel plates to each other in the
same way as in EXAMPLE 8. Furthermore, heat treatment was performed
at 700.degree. C. for 10 minutes.
The bonding strength of the stainless steel plates obtained in the
above manner and the adequacy of metalizing on the stuck surface
was studied. The results are shown in Table 9.
TABLE 9 ______________________________________ Embodiment 9-1 9-2
9-3 ______________________________________ Bonding film paste
evaporated onto surface material of bonded material Bonding 37 34
37 strength (kg) Adequacy of .smallcircle. .smallcircle.
.smallcircle. metallizing
______________________________________
Thus, the polymer composite in accordance with this invention can
be fully applied regardless of the form of the sticking
material.
EXAMPLE 10
It was demonstrated that a polymer composite relating to this
invention has photoelectric effect enabling photo energy to be
converted into electrical energy.
Samples, as shown in FIG. 13, were prepared by the following
process. First, a glass substrate 10 (ITC glass, Central Glass Co.,
Ltd.) with the thin film 11 of indium tin oxide (ITC) laminated to
the glass substrate 10 was placed in a vacuum evaporator, followed
by lamination of a polymer composite 12 to said ITC by the same
method as in EXAMPLE 2; then, it was again placed in the vacuum
evaporator for lamination of the aluminum evaporated film 13 with a
thickness of about 0.2 .mu.m to the surface of the polymer
composite 12, and terminals 14 and 14, respectively, were taken out
from the aluminum evaporated film 13 and the thin film 11 of ITC,
thus enabling the measurement of voltage.
The above-mentioned samples were irradiated with a 50 W halogen
lamp at a light irradiation area of 1 cm.sup.2 from one side of the
glass substrate 10, photoelectromotive force and its build-up
(variation speed immediately after light irradiation) were
measured. The results are shown in Table 10.
In the comparative examples, nylon 11 in bulk, germanium evaporated
film, silicon evaporated film, and nylon 11 evaporated film were
used as substitutes for the polymer composite.
TABLE 10
__________________________________________________________________________
Sample for Thickness of sample Maximum photo- Build-up measurement
for measurement electromotive force (mV) (mV/sec)
__________________________________________________________________________
Embodi- 1 Au-nylon 11 5 .mu.m 157 2.1 ment 10 2 Cu-nylon 11 5 .mu.m
265 6.0 3 Ge-nylon 11 5 .mu.m 260 48.0 4 Si-nylon 11 5 .mu.m 160
155.0 Compara- 1 nylon 11 in bulk 100 .mu.m 0 -- tive 2 Ge
evaporated film 2000 .mu.m 10 23.5 example 3 Si evaporated film
2000 .mu.m 4 22.0 10 4 Nylon 11 evaporated 5 .mu.m 130 0.6 film
__________________________________________________________________________
Thus, in a polymer composite in accordance with this invention, its
electromotive force is found to increase, coupled with a raise in
its variation speed, compared with the comparative examples upon
exposure to light irradiation possessing sufficient photoelectric
effect.
* * * * *